Air exchange ventilation unit



FIG. 1 is a perspective view of an air exchange ventilation unit embodying my new design;

FIG. 2 is a front elevation view thereof, the rear being a mirror image of that shown;

FIG. 3 is a top plan view thereof;

FIG. 4 is a left end elevation view thereof;

FIG. 5 is a right end elevation view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a front elevation view of an air exchange ventilation unit, showing a second embodiment of my new design, the rear being a mirror image thereof;

FIG. 8 is a top plan view of FIG. 7;

FIG. 9 is a right end elevation view of FIG. 7, the left end being the same as that of the first embodiment, as shown in FIGS. 1 and 4; and,

FIG. 10 is a bottom plan view of FIG. 7. 

The ornamental design for an air exchange ventilation unit, as shown and described. 